Charging system

Abstract

The charging system improves the overall charging efficiency of electric vehicles at the charging station. [Solution] A charging system for charging a battery (1) included in a vehicle (10) comprises a first charger (1P) capable of charging the battery using a first power, a second charger (2P) capable of charging the battery using a second power lower than the first power, and a control device (100) that controls the vehicle according to the state of the battery and the temperature of the first charger. When the battery is being charged using the first power from the first charger (YES in S10), the control device controls the vehicle to charge the battery using the second power from the second charger if a power lower than the first power is required from the first charger according to the state of the battery and the temperature of the first charger (S40).

Description

Technical Field

[0006] , , ,

[0001] The present disclosure relates to a charging system, and particularly to charging of an electric vehicle.

Background Art

[0007] With the above configuration, if the charging efficiency of a high-power EVSE decreases, the electric vehicle can be encouraged to use a lower-power EVSE where the charging efficiency does not decrease, and the high-power charger can be relinquished to other electric vehicles that can use it at a high charging efficiency. In this way, the charging system can improve the overall charging efficiency of the charging station for electric vehicles. [Effects of the Invention]

[0008] According to this disclosure, the charging system can improve the overall charging efficiency of the charging station for electric vehicles. [Brief explanation of the drawing]

[0009] [Figure 1] This diagram schematically shows an example of the overall configuration of a charging station to which a charging system is applied. [Figure 2] This figure shows an example of the configuration of an electric vehicle and EVSE according to this embodiment. [Figure 3] This flowchart explains the process of prompting an electric vehicle currently being charged by an EVSE to receive power from the next EVSE. [Modes for carrying out the invention]

[0010] The embodiments of this disclosure will be described in detail below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and their descriptions will not be repeated.

[0011] [Embodiment 1] <Overall configuration of the charging system> Figure 1 is a schematic diagram showing an example of the overall configuration of a charging station St1 to which the charging system 200 is applied. The charging station St1 is equipped with EVSE1P to 7P.

[0012] Each of the EVSE1P to 7P units has vehicle parking spaces on both sides. As shown in Figure 1, EVSE1P is configured to charge electric vehicles parked in parking spaces Sp1 and Sp2. In the example in Figure 1, electric vehicles 10A and 10B are parked in parking spaces Sp1 and Sp2, respectively.

[0013] Hereinafter, electric vehicles that can be charged at charging station St1, including electric vehicles 10A and 10B, will be collectively referred to as "electric vehicle 10". Similarly, EVSEs installed at charging station St1, including EVSE1P to 7P, will be collectively referred to as "EVSE10P". Electric vehicle 10 and EVSE10P are examples of the "vehicle" and "charger" as defined in this disclosure, respectively. Electric vehicle 10 includes, for example, a PHEV (Plug-in Hybrid Electric Vehicle), a BEV (Battery Electric Vehicle), or an FCEV (Fuel Cell Electric Vehicle). Electric vehicle 10 may be a manned vehicle driven by a human driver, or it may be an unmanned vehicle equipped with an autonomous driving system.

[0014] EVSE2P is configured to charge electric vehicles 10 parked in parking spaces Sp3 and Sp4. EVSE3P is configured to charge electric vehicles 10 parked in parking spaces Sp5 and Sp6. Similarly, EVSE4P to EVSE7P are each configured to charge electric vehicles 10 parked in any two of the corresponding parking spaces Sp7 to Sp14.

[0015] The two parking spaces linked by the arrows shown in Figure 1 are arranged to allow the electric vehicle 10 to move smoothly. Parking spaces Sp1 and Sp3 are, for example, adjacent to each other so that the electric vehicle 10A can move from parking space Sp1 to parking space Sp3. Similarly, parking spaces Sp1 and Sp4 may also be arranged adjacent to each other. Each of parking spaces Sp1 and Sp2 is located adjacent to the entrance of a charging station St1 (not shown). Also, each of parking spaces Sp7 to Sp14 is located adjacent to the exit of a charging station St1 (not shown).

[0016] Each of the EVSE1P to 7P is configured to be able to charge the electric vehicle 10 by being electrically connected to it. In the example in Figure 1, the number of EVSEs included in the charging station St1 is 7, but in some situations the number of EVSEs included in the charging station St1 may be other numbers, such as 3, 5, 10, 30, 50, or 100.

[0017] Each of the EVSE1P to 7P has a predetermined maximum charging output that can charge the electric vehicle 10. The maximum charging output of EVSE10P is the upper limit of the power value that EVSE10P can tolerate due to the increase in current and / or voltage in the electrical connection. EVSE1P is a so-called super-fast charger and is configured to charge the electric vehicle 10 with a power value of 350kW or more as the upper limit. EVSE2P and 3P are so-called fast chargers and are configured to charge the electric vehicle 10 with a power value between 50kW and 150kW as the upper limit. The maximum charging output of EVSE2P and 3P is, for example, 100kW. EVSE4P to 7P are normal chargers and are configured to charge the electric vehicle 10 with a power value between 4 and 6kW as the upper limit. The maximum charging output of EVSE2P and 3P is, for example, 5kW. The power value at the maximum charging output of EVSE1P is an example of the "first power" in this disclosure. The power values ​​at the maximum charging output of EVSE2P and EVSE3P are examples of the "second power" as defined in this disclosure.

[0018] EVSE1P can charge the electric vehicle 10 using the highest maximum charging output among EVSE1P to 7P. EVSE2P and 3P can charge the electric vehicle 10 using a lower maximum charging output than EVSE1P, and a higher maximum charging output than EVSE4P to 7P. EVSE4P to 7P can charge the electric vehicle 10 using the lowest maximum charging output among EVSE1P to 7P.

[0019] However, these EVSE1P to 7P cannot continuously charge the electric vehicle 10 using the maximum charging output from the start to the end of charging. For example, when the EVSE1P is charging the electric vehicle 10, if at least one of the State of Charge (SOC) of the battery mounted on the electric vehicle 10 and the temperature of the battery becomes higher than a predetermined threshold, the electric vehicle 10 requests the EVSE1P to reduce the charging output for charging. Also, in the EVSE1P, when the temperature of the EVSE1P becomes higher than a predetermined temperature due to heat generation during charging, the EVSE1P requests itself to reduce the charging output for charging. Therefore, even when supplying power to the electric vehicle 10 using the EVSE1P, the period during which it is actually possible to supply power of 350 kW or more is only within a predetermined period after the start of charging.

[0020] Therefore, in the charging system 200 of the present embodiment, when it is detected that the high-output EVSE10P cannot charge at the maximum charging output while charging the electric vehicle with the high-output EVSE10P, charging using the low-output EVSE10P is started for the electric vehicle 10. Thereby, the charging system 200 can improve the charging efficiency of the electric vehicle 10 as a whole charging station. In the example of FIG. 1, the electric vehicle 10 that has entered the entrance of the charging station St1 sequentially moves from the high-output EVSE10P to the low-output EVSE10P.

[0021] <Configuration of Electric Vehicle and EVSE> FIG. 2 is a diagram showing an example of the configuration of the electric vehicle 10 and the EVSE10P in the present embodiment. The EVSE10P includes a cable 20b to which a connector 20a is attached. When the connector 20a is connected to an inlet (not shown) of the electric vehicle 10, power is transmitted (charged) from the EVSE10P to the electric vehicle 10.

[0022] The electric vehicle 10 includes an ECU (Electric Control Unit) 100, a battery pack 1, a sensor 2, and a notification unit 3. The battery pack 1 stores, for example, the electric power used for the running of the electric vehicle 10. The battery pack 1 can increase the stored amount of electricity by charging from the EVSE10P. Note that the battery pack 1 is an example of the "battery" in the present disclosure.

[0023] The ECU 100 transmits and receives information to and from the battery pack 1, the sensor 2, the notification unit 3, etc. through CAN communication or the like by the communication unit 130 described later. The ECU 100 includes a processor 110, a memory 120, and a communication unit 130. In the memory 120, in addition to the programs executed by the processor 110, information used in the programs (for example, variables for storing the detection values of the sensor 2, maps, mathematical formulas, and various parameters, etc.) are stored. Note that the ECU 100 is an example of the "control device" in the present disclosure.

[0024] The ECU 100 is configured to be able to acquire at least one of the SOC of the battery pack 1 and the temperature of the battery pack 1 using the sensor 2. The sensor 2 includes, for example, at least one of a sensor for acquiring the voltage value of the battery pack 1 and a sensor for acquiring the temperature of the battery pack 1. In the memory 120, a map showing the relationship between the voltage (OCV: Open Circuit Voltage) of the battery pack 1 and the SOC is stored. The ECU 100 calculates the SOC of the battery pack 1 based on the map and the detection value of the sensor 2. Note that the method for calculating the SOC is not limited to the above example.

[0025] When the electric vehicle 10 is a vehicle driven by a human driver, the notification unit 3 gives a notification to the driver, and when the electric vehicle 10 is a vehicle equipped with an automatic driving system, the notification unit 3 gives a notification to the automatic driving system. The communication unit 130 transmits and receives information to and from the EVSE10P through the cable 20b in a state where the connector 20a is connected to the electric vehicle 10.

[0026] The EVSE10P includes a processor 21, a memory 22, and a communication unit 23. The memory 22 stores a program executed by the processor 21, as well as information used by the program (for example, variables, maps, formulas, and various parameters that store the detected values ​​of the sensor 24). The sensor 24 is a temperature sensor that detects the temperature of a part of the EVSE10P that generates heat during charging. The sensor 24 may, for example, detect the temperature of a circuit inside the EVSE10P, or it may detect the temperature of a cable 20b or a connector 20a. The ECU 100 can obtain the detected values ​​of the sensor 24 via the communication unit 130.

[0027] <Processing Procedure> Figure 3 is a flowchart illustrating the process of prompting the electric vehicle 10, which is being charged by EVSE1P, to be powered by the next EVSE10P. The flowchart shown in Figure 3 is implemented by the ECU100 executing a program stored in memory 120. The ECU100 repeatedly executes the flowchart shown in Figure 3.

[0028] The ECU 100 determines whether the battery is being charged from an EVSE 10P other than the one with the lowest upper limit of the acceptable power value (step S10). That is, the ECU 100 determines whether the battery is being charged from any of EVSE 1P, 2P, or 3P. The ECU 100 performs the process in step S10 based on information such as the EVSE 10P information obtained via the communication unit 130, whether the connector 20a is connected, and whether the amount of charge stored in the battery pack 1 is increasing.

[0029] If charging is not occurring from any of EVSE1P, 2P, or 3P (NO in step S10), the ECU100 terminates the process shown in the flowchart in Figure 3. If charging is occurring from any of EVSE1P, 2P, or 3P (YES in step S10), the ECU100 acquires at least one of the detected values ​​from sensor 2 and sensor 24 (step S20).

[0030] The ECU 100 determines, based on at least one of the detected values ​​of sensor 2 and sensor 24, whether the power requested from EVSE 1P, 2P, or 3P is less than the maximum charging output (step S30). Specifically, for example, when at least one of the following is true: the State of Charge (SOC) of battery pack 1 has risen above a predetermined threshold, the temperature of battery pack 1 has risen above a predetermined threshold, and the detected value of sensor 24 has risen above a predetermined temperature, the ECU 100 requests power less than the maximum charging output.

[0031] If the ECU 100 requests the maximum charging output (NO in step S30), it terminates the processing of the flowchart in Figure 3. If it requests less power than the maximum charging output (YES in step S30), the ECU 100 prompts the electric vehicle 10 to move to the next space (step S40). That is, the ECU 100 causes the notification unit 3 to notify the electric vehicle 10 to move to the next space. For example, if the electric vehicle 10 was charging in parking space Sp2, the ECU 100 prompts it to move to parking space Sp5 or parking space Sp6.

[0032] In another example, if electric vehicle 10 is charging in parking space Sp4, the ECU 100 prompts it to move to parking space Sp9 or parking space Sp10. At this time, the ECU 100 may obtain the parking status of other electric vehicles 10 at charging station St1 from the EVSE 10P. If the parking status of other electric vehicles 10 is obtained, the ECU 100 may check the parking status of other electric vehicles 10 in parking spaces Sp9 and Sp10 and prompt it to move to a space where no other electric vehicles 10 are parked.

[0033] Thus, the charging system 200 in this embodiment can suppress an increase in the period of low charging efficiency during which each EVSE 10P cannot be charged at maximum charging output by prompting the movement of the electric vehicle 10 when the charging efficiency decreases. As a result, the charging system 200 can improve the charging efficiency of the electric vehicle 10 as a whole for the charging station St1.

[0034] <Variation> In the above-described embodiment, the execution entity of the flowchart in Figure 3 was explained as being the ECU 100. However, the execution entity of the flowchart in Figure 3 may be the processor 21 of the EVSE 10P or the processor of an external server (not shown).

[0035] In the example described above, it was explained that EVSE10P units with three types of maximum charging output are installed at charging station St1. However, the number of EVSE10P units installed at charging station St1 may be two types or four or more types.

[0036] In the example described above, charging is performed via cable 20b, but a contactless power supply method may also be applied. In the example described above, the electric vehicle 10 itself moves between EVSE 10P, but the electric vehicle 10 may be transported to each EVSE 10P by the movement of the road. The notification unit 3 may not notify the driver, but rather the employees of the charging station St1. The charging station St1 may be installed in urban areas, highway service areas, roadside rest areas, etc.

[0037] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of symbols]

[0038] 1 Battery pack, 2,24 Sensors, 3 Notification unit, 10,10A,10B Electric vehicle, 20a Connector, 20b Cable, 21,110 Processor, 22,120 Memory, 23,130 Communication unit, 200 Charging system, St1 Charging station, S1~S14 Parking spaces.

Claims

[Claim 1] A charging system for charging the battery included in a vehicle, A first charger capable of charging the battery using the first power, A second charger capable of charging the battery using a second power lower than the first power, The vehicle is equipped with a control device that controls the vehicle according to the state of the battery and the temperature of the first charger, A charging system comprising: a control device which, when the battery is being charged using the first power from the first charger, controls the vehicle to charge the battery using the second power from the second charger if, depending on the state of the battery and the temperature of the first charger, a power lower than the first power is required from the first charger, depending on the state of the battery and the temperature of the first charger.

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